The growth of photovoltaic arrays on building roofs has skyrocketed in recent years. As consumer demand for installing photovoltaic arrays continues to rise, companies are racing to meet customer demand. The quicker the array can be assembled on the customer's roof, the more profitable the whole operation becomes. As a result, demand currently exists for systems to quickly and efficiently hoist the photovoltaic modules up onto the roof.
Traditionally, photovoltaic modules may be lifted either by large, expensive motorized hoists, or even by crane. Use of such large, motorized systems add costs to the installation of the array. Moreover, simply lifting modules up a ladder without using a hoist can result is dropped modules. Pulling modules upwardly with a rope is also unsafe (especially in high winds), and ergonomically not desirable.